The present inventions are a result of further research and development of the "Articulated Truck/Trailer Combination" set forth in U.S. Pat. No. 4,475,740 which is assigned to the assignee to the above-identified inventions and incorporated herein by reference.
The most significant problem in the design of the U.S. Pat. No. 4,475,740 truck/trailer combination is the failure of the drawbar which connects the second cargo-carrying unit to the first cargo-carrying unit. Specifically, the failure of the drawbar was due to the connection of the drawbar to the floor of the first cargo-carrying unit. Additionally, the power unit and first cargo-carrying unit have been re-designed to improve the lateral and vertical stability of the entire combination, so as to assure highway safety.
Other tractor/trailer combinations are known which utilize at least two cargo-carrying bodies and are pivotally connected to each other. For example, in U.S. Pat. No. 3,237,966 (Ayers), there is shown a combination of vehicles including a tractor having a trailer body rigidly secured thereto by a coupling or hitch so that the body is closely adjacent the tractor cab, like in a truck. A trailer body is connected to the truck body by a conventional hitch.
In U.S. Pat. No. 3,484,852 (Norrie et al), there is shown a combination vehicle comprising a tractor on which a trailer body is secured, a second trailer is connected to the body of the first trailer, via a tow bar and eye.
In U.S. Pat. No. 3,841,511 (Haun), there is shown a combination vehicle comprising a first modular cargo body releasably secured on the frame of a tractor and a second similar body mounted on a pair of carriage units. The front carriage unit is connected to the frame of the tractor via a drawbar.
In U.S. Pat. No. 4,303,258 (Davis), there is shown an improved animal carrier wherein a pick-up truck having an animal enclosure thereon is connected via a hitch to a trailer. The forwardmost portion of the trailer includes a pair of doors and a walk ramp which extends from the trailer to the rear of the pickup truck. Accordingly, the trailer/pickup combination has a complete walk through cargo space.
In U.S. Pat. No. 3,163,306 (Bennett et al) a multiple unit trailer and containers are disclosed. A power unit having a cab mounted on a chassis front wheel disposed under the cab and rear wheels mounted on the chassis and a fifth wheel located adjacent said rear wheels. A dolly having a pair of wheels, a fifth wheel located above the pair of wheels, and a kingpin for engagement with the fifth wheel of the power unit is adapted to receive containers thereon. A second semi-trailer having landing gear, rear wheels located at the rearward most end of said trailer and a kingpin for engagement with the fifth wheel of said dolly is adapted for receipt of containers thereon. In FIG. 5, landing gear 52 for dolly 14 is disclosed. In FIG. 13, tapered plug 75 are disclosed. Tapered plug 75 engage with tapered slots 50 to secure rear semi-trailer 16 to truck dolly 14.